Method of marking polished glass articles



p 1937. 'r. a. DRESCHEE METHOD OF HARKING POLISHED GLASS ARTI [CLES F119; Nov. 22, 19:54

THEODORE. B. DRESCHER mvsmon ATTORNEY Patented Sept. 21, 1937 PATENT C METHOD or MARKING rousnsn ARTICLES cuss Theodore B. Drescher, Brighton, N.-'Y., assignor to Bausch & Lomb optical. Company, Rochester, N. Y., a corporationioi New York ApplicationNoveinber 22, 1934, Serial N usea; 6 Claims. (01. 41-,.-2s

This invention relates to identification or trade marking of glass articles such as lenses and mirrors, for example.

In the sale of glass articles such as spectacle lenses, for example, itis. highly desirable that the manufacturers trade-mark or name shouldremain on the goods until they are delivered for .use to the ultimate consumen. It has been prof posed to affix to the lens agummed label bearing 1:) the manufacturer's name or trade-mark. However, this label is very likely. to be accidentally removed while the dispensing Optician surfaces, edges, cuts, drills or mounts the lens in the spectacle frame or mounting." During the time that the lens, whether in semi finished or finished form, is being operated upon by the optician by surfacing, edging, cutting, drilling or mounting it will usually come in contact with one or more of the following substances: soapand water, alkalies.

alcohol, turpentine} kerosene, gasoline, mineral oils, and/or one of the following pitch solvents such as ethanol, benzol, carbon tetrachloride, dichlorethylene and trichlorethylene. Hence, if reasonable assurance is to be had that the trademark willremain on the lens until delivered to the ultimate consumer,v the mark must be ap--' pliedto the lens by meansofa substance-which will adhere. firmly 'to the glass even in the pres:-

ence ofwater or alkalies and be relatively hard and resistant to theaction of the usual substances which it might encounter in the opticians shop...

The mark should, however, be capable of being readily removed by the optician, without destroying or affecting the polished surface, just before the finished spectacles are delivered to the wearer. The removal of the mark should, of course, preferably be accomplished in the presence of the wearer so that he will be informed as tothe name of the manufacturer and the quality of the lenses he is purchasing. I

One of the objects'of my. invention is to provide an improved' method of identifying glass articles. Another object is to provide animproved method of identifying spectacle lenses by applying thereto a substance which. will withstand the usual treatment of I the opticians shop but which may be readily removed by certain substances. A further object is to provide. an oph- 5o thalmic lens having deposited on a surfacethereof indicia which will adhere firmly to the. glass in the presence of water and will be resistant to attack by water, alkalies or a single organic solvent. These and other objects'and advantages 55 reside in certain novel features as'will hereinafter be-more fully described and pointed out in the appended claims.

' Referring-to the drawing: I

Fig. 1. is a front view of a lens marked according to this invention. 5 Fig. 2- is an enlarged fragmentary section' thereof. I 1

An. article marked in accordance with this in-- vention is illustrated in the drawing wherein l0 designates a lens stampedwith a resinous paint I i 10 in any desired design such as that inrFig'. I. This paint adheres closely to the surface of the lens; but, as shown in Fig. 2, it does not change the character of thesurface and remainsentirely separate and distinct from the material 15 comprising the lens. v y

In practicing my. invention by a. preferredmethod I make this paint by dissolving 3-. glycerol phthalate resin in ethanol and benzol and adding range as a pigment. With-this 'paint-and'a rub- .2

her. stamp, stencil or brush, indicia; such as the manufacturer's trade-mark or name, are applied 'to the polished surface. of the lens. 'The lens is then placed'inan oven andheated up to a temperature of 400 degrees Fahrenheit. This ternperature, of course, is not high enough to soften. the glass or destroy the finished polished surface on'the'IensL. The marked lens is held at thistemperature until polymerization of the resinis care ried to apoint where the resin becomes substan- 3o tially insoluble in all of the usualsolvents with which it would come incontact in the normal processing and flnishingo'perations. V

. The' polymerization of the glycerol phthalate is stopped-by removing the marked article from 35 the oven, before the paint becomes insoluble in a mixture; of benzoland ethanol. After such treatment,the .mark will adhere strongly to the lens or otherarticle and willresist the action of alkalies, soap, mineral oils, gasoline, kerosene, 49 carbon tetrachloride, dic hlorethylene, trichlorethylene, turpentine, blocking pitch, water, benzol and ethanol when applied. separately. This in the caseof anophthalmiclens the lens can bc finished and 'marked on -one side by the manufacturer and the subsequent acts of the optician in finishing and mounting the lens will notfremove the mark.-

' By stopping the polymerization ofthe-giycerol phthalate base while it is still soluble in a mixture of benzol and ethanol, themark is left in such condition that it can easily and quickly be removed. In the case of an ophthalmic lens, the dispensingoptician leaves the mark upon the 7 lens until the eyeglasses or spectacles are finished ll and are to be fitted upon the purchaser. In this way the purchaser can see on the lens the name or mark of the manufacturer and the quality of the lens. Before the lenses are to be used, the optician dampens the mark with the mixture of benzol and ethanol, and the mark can then be readily wiped from the lens. The mark is merely on the surface of the lens and hence its application and removal do not affect the finish of the polished lens surface.

Equivalent marking solutions can be made by dissolving glycerol phthalate in other solvents and by using other pigments. A mixture of glycerol phthaiate with Vermilion in ethylene glycol monomethyl ether makes a very satisfactory marking fluid. A mark made with this fluid is baked at a temperature between 375 and 500 degrees Fahrenheit. Here again the polymerization of the resin is controlled so that it issoluble only in certain solvents. This solubility can be regulated so as to include solvents other than the mixture of ethanol and benzol. Ethylene glycol monomethyl ether is a suitable solvent when the polymerization of the resin has been stopped at a suitable point.

From the foregoing. it is apparent that I am able to attain the objects of my invention and provide amethod of identifying an ophthalmic lens which will withstand the usual treatment of the optician's shop but which may be easily and readily removed by certain suitable solvents and also provide a lens so marked. Various modifications can, of course, be made without departing from the spirit of my invention or the scope of the appended claims.

I claim:

1. The method of identifying a glass article which comprises marking said article with a soluble glycerol phthaiate paint, and heating the marked article until the paint is polymerized to a predetermined extent.

2. The method of identifying a glass article which comprises marking said article with glycerol phthalate which is soluble in several single solvents and heating said marked article until the glycerol phthalate mark is soluble only in a mixture of single solvents.

3. A method of treating an ophthalmic lens having a polished surface which is to be unobstructed when in use which comprises applying indicia to said surface by depositing thereon a glycerol phthalate resin, heating the lens to approximate 1y 400 degrees Fahrenheit to render the indicia resistant to certain solvents, operating upon the lens to adapt it for use before the eye and then removing the indicia with a mixture of organic solvents, without affecting the poilshed surface, so as to render the lens fit for use before the eye.

4. A method of treating a glass article having a polished surface which is to be unobstructed when in use which comprises applying indicia to said surface by depositing thereon a glycerol phthalate resin and heating the article to approximately 400 degrees Fahrenheit. whereby said indicia 'firmly adheres to the surface and becomes resistant to alkalies, and finally removing said indicia with a mixture of organic solvents before the article is used.

5. An ophthalmic lens or the like having a ground and polished surface. and identification means on said surface comprising a polymerized glycerol phthalate resin.

6. An ophthalmic lens or the like having a ground and polished surface, and identification means on said surface comprising a glycerol 1 phthaiate resin which has been polymerized to a predetermined extent by heating to approximately 400 degrees Fahrenheit.

THEODORE B. DRESCHER. 

